JP2002203360A - Recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that the electric power of motors during operation cannot be reduced and that the wait time until starting is long in a power saving-type recording and reproducing device used for personal computers, etc. SOLUTION: A recording and reproducing device having a high electric power reduction effect during operation and short start-up time is obtained by providing a motor revolution speed change part 55 in an electric power control section 9; increasing or decreasing the number of rotations of the motor 8 on the basis of the start-up or pause control signal from a computer 100 or cache residual amount information from a cache memory monitor part 64; and carrying out the low-speed revolution.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus using a recording medium.

[0002]

2. Description of the Related Art In recent years, some recording / reproducing apparatuses used for personal computers and the like have a power saving function. The conventional method is to stop the rotation of the motor rotating at a constant angular speed when there is no request for data recording and reproduction for a certain period of time, start the motor when requested, and rotate it again at the set number of rotations. Have been. Therefore, when there is a request for data recording / reproducing, a 3 inch disk with a small diameter is used until the mode changes from the stop mode to the operation mode.
Second, it takes about 5 seconds for a 3.5-inch medium-diameter disk, so that there is a problem that a long waiting time is required for reading and writing data. 6000r. p. There is a problem that recording and reproduction can be performed only at a specific fixed number of revolutions such as m, and the power of the motor cannot be reduced during operation.

[0003]

However, in the conventional configuration, recording and reproduction are performed by rotating the recording medium at one constant number of revolutions. Therefore, there are only two modes of the rotation state in which the rotation of the motor is stopped and the rotation state in which the motor is started. Could not be selected. Therefore, not only is the width of power saving small, but also since recording and reproduction cannot be performed at all until a predetermined number of revolutions is reached, there is a problem that a waiting time of several seconds is required from stop to recording and reproduction.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and has the advantages of both reducing the power of the motor in the operating state during recording and reproduction and having a shorter waiting time for reading and writing data during the power saving operation. It is an object to provide a playback device.

[0005]

In order to achieve this object, a recording / reproducing apparatus according to the present invention comprises a recording medium, a rotating motor for rotating the recording medium, a recording / reproducing head, a recording / reproducing circuit, and an external input / output unit. When the recording medium is rotated by the rotating motor to record and reproduce a recording signal on the recording medium by the recording and reproducing head, and when a state in which the amount of recording and reproducing data to be recorded and reproduced continues for a certain period of time, the rotating motor The recording / reproducing apparatus for stopping or starting the operation has a configuration including a power control unit, a motor rotation speed changing unit, and a recording / reproducing clock reproducing unit.

According to this configuration, the motor rotation speed is reduced by the motor rotation speed changing unit in the power saving mode, and the PLL center frequency of the recording / reproducing clock reproducing unit is increased / decreased in conjunction with the rotation speed, so that at the time of low speed rotation. Can be stably recorded and reproduced. In this way, the power can be reduced even during operation, the substantial waiting time until startup can be reduced, and the data access time can be shortened.

[0007]

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a recording and reproducing apparatus according to a first embodiment. The present invention is effective for an optical recording device as well as a magnetic recording / reproducing device.
The principle will be described.

The recording / reproducing apparatus 1 includes a recording medium 3 such as a magnetic disk having a recording layer 2 on which information is recorded as a magnetic recording signal 4. This recording medium 3 is a motor drive circuit 7
The motor is rotated by a rotation motor 8 driven by the motor. The magnetic recording signal 4 is recorded or reproduced by the magnetic head 5. The recording / reproducing unit 6 demodulates a reproduction signal of the magnetic head 5 into a digital output signal, modulates a digital input signal into a magnetic recording signal, and sends the signal to the magnetic head 5.

[0010] The configuration described above includes the same parts as the conventional system. The feature of the present invention is that, in the case of a conventional type hard disk, recording and reproduction are performed in a CAV in which a recording medium is rotated at a specific constant rotation speed or a constant linear velocity, or in a zone CAV or a zone CLV. The rotation speed of the rotation motor 8 is reduced by the power control unit 9,
The power consumption is greatly reduced by performing recording / reproducing or lowering or stopping the operation clock frequency of each digital circuit unit in conjunction with the deceleration.

As shown in FIG. 6 showing the relationship between the flying height of the slider and the number of revolutions, in the system in which the slider is simply pressed with a constant spring pressure W _SC , when the rotation motor 8 is decelerated as shown by the spring characteristic 51b, the landing revolution number N _{At L} , the flying force and the spring pressure W _SC become substantially equal, and the flying distance 11 between the slider 10 and the recording medium 3 becomes extremely narrow. Since the recording medium 3 has irregularities, the magnetic head 5 and the recording medium 3 come into contact with each other, and the recording layer 2 is destroyed, so that data cannot be recorded or reproduced.

On the other hand, in the first embodiment, as a first method, a slider flying height control unit 15 is provided in a central control unit 13 together with a recording / reproducing track changing unit 14 as shown in FIG. Is reduced, the flying height of the slider is controlled so as to ensure a constant flying height of the slider.

As shown by a spring characteristic 51a in FIG.
The first method is the motor rotation speed N or the head and media.
Slider flying height control unit as the relative velocity V of the
15 by a slider press changer 16 controlled by
Spring pressure W of rider spring 17 _SCIs lowered. This
And the head flying height h even when the rotation motor is decelerated.₀Decrease
Is relaxed. Therefore, even if the rotation speed N becomes 1 / n,
The rider 10 floats and the recording head 5 even at low speed rotation.
Recording and reproduction can be performed without contact between the
You.

FIGS. 9A and 9B show this state.
(C), (d) and (e), where R = 1, １ ／, ４,
The change of the spring force of the slider spring force and the flying force of 1/8 and 0 is shown.

In this case, for example, when the spring pressure W _S shown in the case of R = 1/8 in FIG. 6 is reduced to secure the flying height h ₀ , the spring force due to the floating force and the slider spring force are weak.
Vulnerable to external impact.

Therefore, in a personal computer such as a notebook personal computer which can be used for portable use, if the rotation speed is reduced to 1 / n times for power saving, the floating spring force and the slider spring force are weak, so that the external force is reduced. The shock may cause the slider 10 and the recording layer 2 to come into contact with each other, thereby destroying data. In the present invention, the external impact force is detected by the G sensor 18, and when G having a magnitude equal to or more than the second level is detected, the magnetic head 5 is retracted to the retreat track 12 a shown in FIG. Stop the rotation to protect the recording layer.

[0017] If the if detects a second level of the first level or more or less the size of G, in t = t _8x from t = t _a in FIG. 10 (C), the example the rotational speed of the motor 1/8 When the distance is increased from to 力, the floating force and the force of the slider spring become strong, and during t = t _{a to} t ₁₀ , it can withstand a moderate external impact. When the detection signal of the G sensor 18 decreases and continues for a certain period of time, it is determined that the external impact has decreased, and t = t ₁₁
, The operation returns to the power saving mode of R = 1/8.

The first method of reducing the strength of the slider spring 17 by the slider pressing changer 16 in accordance with the number of rotations and maintaining the head floating is large because it can cope with the case where the motor rotation speed is widely reduced. There is a power reduction effect.
Further, by providing the G sensor 18, the support spring force of the slider 10 can be increased or decreased by changing the rotation speed N in accordance with external vibration, thereby preventing the recording layer 2 from being broken due to contact with the slider 10. .

Next, the second method will be described. When it is not necessary to increase the deceleration width of the motor rotation, FIG.
As shown in the slider cross-sectional view and the perspective view of FIG. 2B, a concave negative pressure generating portion 81 is provided on the sliding surface of the slider 10. As a result, as shown in FIG. 15, as the linear velocity V increases, as shown by the solid curve 30a, even if the linear velocity V is increased as compared with the curve 30b shown by the dotted line of the normal positive pressure slider, FIG. the negative pressure F _N shown in a), the flying height of the slider is suppressed. Therefore, as shown by the curve 30a in the relationship diagram between the linear velocity and the slider flying height in FIG. 15, the slider flying height is kept in a substantially constant range with respect to the rotation speed N. FIG.
In the case of, the reference flying height is set to 0.2 μm, and is within ± 0.5 μm even if the speed is reduced from the same speed to 1/4 speed, indicating that recording and reproduction are possible. .
Although the range of the deceleration is slightly narrowed, the use of the negative pressure slider eliminates the slider pressing adjustment unit and can cope with the deceleration even if the slider is pressed with a constant slider pressing.

As described above, by combining the negative pressure slider system and the power saving system, the slider 10 does not come into contact with the recording medium even if the rotation speed of the motor is reduced, so that the power of the motor can be reduced. it can.

As a third method, a negative pressure slider 10 having a negative pressure generating portion as shown in FIG.
By combining the slider pressing changer 16 shown in FIG. ₁ , a more stable flying height h ₀ of the slider 10 can be obtained. According to this method, even if the value of n of R = 1 / n, that is, the reduction ratio is increased, the fluctuation of the flying height of the slider is small. For this reason, the recording and reproduction can be performed without the slider 10 coming into contact with the recording medium 3 even at the low speed rotation of 1/8 times speed or 1/10 times speed. For this reason, recording and reproduction can be performed at a low rotation speed, so that power consumption can be further reduced.

Here, a method of changing the pressing of the slider will be described. As shown in a perspective view of the system in FIG. 11, the four sliders 10a, 10b, 10c, and 10d are attached to head arms 20a, 20b, 20c, and 20d, and tracking control is performed by a track driving unit 19. The track driving unit 19 includes a tracking motor 19.
aA slider press changer 16 is provided as shown in FIG. 12, and when the arm elevating shaft 23 is rotated clockwise in the direction of arrow 24, the arm elevating parts 21a and 21c advance upward, and the arrows 24a and 24c The directional force pushes the slider arms 20a and 20c, and the slider pressing force decreases. On the other hand, the arm elevating portions 21b and 21d advance downward, and the slider arms 20b and 20d have arrows 24b,
A force in the 24d direction is applied, and the slider arms 20b, 20
The slider pressing force of d is similarly reduced. On the other hand, when the slider pressing change section 16 is turned in the opposite direction, the slider pressing force increases. Thus, the slider pressing can be controlled to an arbitrary value.

Next, recording and reproduction will be described. Recording signal M
In the case of the R head, the detected signal is as shown in FIG. On the other hand, in the case of a ring head, the result is as shown in FIG. The detected signal is supplied to a reproducing circuit 25 of the recording / reproducing unit 9.
, And a reproduced clock signal as shown in FIG. 2E is reproduced by the PLL 27 in the clock reproducing unit 26. The digital signal as shown in FIG. 2 (f) is punched out by the punching section 38 of the demodulator 28 based on the reproduced clock signal.

In the case of the first embodiment, the rotation speed at the time of recording and reproduction is very wide, such as 1, 1/2, 1/4, and 1/8. Therefore, the recording / reproducing clock also fluctuates greatly as shown in FIG. In the first embodiment, since the pull-in range of the PLL 27 of the recording / reproduction clock reproduction unit 26 of the reproduction circuit 25 is widened, the reproduction clock is reproduced quickly. The synchronization signal recorded in the address area is reproduced, or a rotation pulse corresponding to the rotation speed of the recording medium is obtained from the motor rotation pulse from the rotation pulse generator 8a of the motor 8, and is shown in FIG. The reference center frequency 34 of the reference clock signal generator 2a is set to an appropriate value according to the rotation speed of the recording medium. For example, as shown in FIG. 3B, at the time of 1/8 rotation, the pull-in center frequency is f _n = f ₈
controlled to be b f _1/8. Specifically, the pull-in center frequency control unit 29 controls the VCO 30 according to a recording medium rotation pulse corresponding to the recording medium rotation speed. After passing through the frequency divider 31, f _n = f ₈ . R = 1/8, 1/4, 1
/ 2, 1 for the pull-in center frequency 34d of the PLL,
34c, 34b and 34a are as shown in FIG.
The optimal value is set according to the rotation speed of the recording medium 3. As shown in FIG.
Because LL pull the center frequency f _n is set to continuously optimum value according to the recording medium speed recording reproduction clock in a short time from the reproduction signal is drawn, there is an effect that is generated.

At the time of recording, in order to obtain a recording / reproducing clock corresponding to the number of revolutions from the recording / reproducing clock reproducing section 26 in the same manner, even if the number of revolutions is continuously changed, the recording medium 3 is kept at the set recording wavelength. The recording signal is recorded on the recording medium. Thus, recording is basically performed even while the rotation speed is continuously changed. Since the entire time during the rotation of the motor can be used for recording, the time utilization efficiency is high and the power saving effect is high.

Next, a method for further reducing the error rate during recording will be described. Since recording requires higher accuracy than in the case of playback, recording while the rotation speed is continuously changing has a high power saving effect, but for applications that require reliable recording. Is not preferred. Therefore, in such an application, as shown in FIG. 10 (c), reproduction is performed even during rotation speed fluctuation, but recording is performed at R =＝, ４, 、,
There is also a second method which is performed in a constant angular velocity state such as 1. In this method, the power saving effect is slightly reduced, but there is an effect that recording with a lower error rate can be performed.
At the time of reproduction, data access needs to be performed quickly, but at the time of recording, there is no problem even if data recording is performed later as long as recording is performed reliably. In the first embodiment, the recording cache memory 6
By storing a fixed amount of recording data in 3a, the number of times of mechanical magnetic recording is reduced by the power control unit 9. The data to be recorded is actually written in the cache memory until the recording cache memory 63a reaches the prescribed amount by the cache memory monitoring unit 64 and before the recording data arrives. Treat as recorded. During this time, there is no mechanical power consumption and the power consumption of the electronic circuit is lower, so that the overall power consumption is reduced. In this way, the mechanical operation of several recordings is omitted.
When the recording cache memory 63a reaches the set value, the data to be recorded stored in the recording cache memory 63a is sent to the recording / reproducing unit 63a, and is actually recorded on the recording medium 3.

Since the recording cache memory 63a is used as a buffer memory at the time of recording, a certain amount of remaining memory is always secured. This remaining memory is shown in FIG.
When greater than the recording data transfer rate of the data rate of the recording data R = 1/8 when being recorded with R = 1/8 as shown in t = t ₁₅ of (c), stored in the remaining memory section By doing so, recording can be performed at a low rotation speed of R = 1/8, and it is not necessary to increase the rotation speed, thereby saving power.
When the data rate of the recording data is too high and the remaining buffer capacity is small, the rotation speed is increased to R = １ ／ or R = １ ／ to increase the remaining memory capacity. As described above, the power control unit 9 performs a fine power saving operation to reduce power.
The recording cache memory 63a and the cache memory monitoring unit 64 reduce the number of rotations during recording and reduce the actual recording frequency, which has the effect of reducing motor power. Even if the power is turned off by the memory backup unit 69, the data stored in the recording / cache memory 63a is backed up, so that the data saved when the power is turned on again is recorded on the recording medium 3, so that the data is reliably recorded.

The reproduction cache memory 63b stores frequently-reproduced data such as the data of the previously read track. Therefore, when reproducing these data again, it is sufficient to reproduce the data in the cache memory.
Since mechanical reading can be omitted, there is an effect that power can be reduced.

Next, returning to the reproducing method, the reproducing circuit will be described in more detail with reference to FIG. Reproduction circuit 25
Comprises a recording / reproducing clock unit 26.

The reproduced signal from the head is first
Cut-off frequency f_cLPF with
The high frequency component is cut by 35. During playback, this
LPF plays an important role. Conventional normal hard disk
In the case of a drive, as shown in FIG.
F_cIs fixed. But the book
In the case of the invention, the number of revolutions is greatly varied for power saving.
Therefore, for example, when the rotation speed is 1/8, 1/4, and 1/2,
In this case, as shown in FIGS. 4B, 4C, and 4D, f _cTo f_c
/ 8, f_c/ 4, f_c/ 2 and frequency f_cBy the changer 36
The filter characteristics of the head amplifier are continuously changed. L
By continuously changing the PF 35 according to the number of rotations,
Optimized filter characteristics at all speeds
Therefore, stable signal reproduction is possible even if the rotation speed is changed.
There is an effect that it becomes effective. Head amplifier amp width MR
In the case of a read signal, the reproduced signal is differentiated by the differentiator 37 and struck.
Punching out by the recording / reproducing clock in the punching section 38
The digital signal is demodulated. The signal waveform in this case is
FIG. 2D and FIG.

Next, the reproducing head will be described. As shown in the relationship between the output of the magnetic head and the linear velocity in FIG.
Higher output than the head is obtained. However, as the rotation speed of the recording medium 3 decreases, the output gradually decreases. As shown in FIG. 18, when the number of rotations becomes 1/8, the output voltage also becomes 1/8, and the output voltage drops by about 20 dB. If this drop occurs, the error rate increases, and it becomes difficult to reproduce a normal digital signal in a computer application. On the other hand, as shown by the output curve 40a of the MR head, the output of the magnetic head 5 of the shield type MR head is lower than that of the ring type head when the rotation speed is high. However, since the reproduction output does not drop in principle even when the rotation speed becomes lower, the output of the MR head is higher than that of the ring head.

In the first embodiment, reproduction is performed in a state where the number of revolutions is greatly reduced for power saving. However, since an MR head is used, a high reproduction output can be obtained even when the number of revolutions is reduced.
There is an effect that data reproduction with a low error rate can be performed even in the low-speed rotation power saving mode.

In the first embodiment, as shown in FIG. 18, since a shield type MR head having a higher output than a yoke type MR head is used, more stable reproduction can be performed. As shown in the perspective view of the shield type MR head in FIG. 17, in the first embodiment, the MR whose magnetic resistance (MR) changes due to the magnetic field.
Since the element 41 is provided perpendicular to the running direction of the medium 5 and a shield type MR head provided with shields 44a and 44b on both sides to eliminate the influence of external noise, the reproduction output is high. By supplying a current to the MR element 41 by the bias voltage section 42 and measuring the magnetic resistance by the magnetic resistance measuring section 43, the magnetic recording signal can be reproduced by measuring the change in the magnetic resistance.

FIGS. 7A and 7B show the MR reproducing head 5a.
And a state where the ring-shaped magnetic head 5b is incorporated into one slider 10. When rotating at high speed, FIG.
As shown in the figure, the flying height h ₀ (1) is large. During low-speed rotation, the flying height h ₀ (1 / n) is reduced even if the flying height is controlled as shown in FIG. 7B. Accordingly, the output of the MR head 5a does not decrease at the time of low-speed rotation.
It is slightly larger than the case of 1. By using the MR head 5a and the ring head in combination as described above, there is an effect that a sufficient reproduction output can be obtained even when the number of rotations is reduced.

At the time of recording, the ring magnetic head 5b is used. When the rotation speed is reduced to 1 / n as described above,
The flying height h ₀ (1 / n) is reduced, and the space loss is reduced, so that the recording efficiency is improved. Therefore, the recording circuit 4 of FIG.
Since the magnetic recording can be performed even if the recording current of the recording circuit 47 of No. 5 is reduced, the power for recording can be reduced. In particular, in the case of the present invention, as shown in the case of R = 1/4 in FIG. 2 (e), the recording / reproducing clock frequency is lowered, and the power consumption of the digital circuit is reduced. Down to a large width.

The recording / reproducing section 6 includes a reproduced digital signal reproduced and a digital processing section 52 for processing a recorded digital signal for recording. The digital processing section 52 performs data error checking, error correction, time axis correction, and the like. Is going. The digital processing section 52 includes a recording / reproducing processing section 53 and an interface section 54. Among them, the data rate of the information amount to be processed by the recording / reproducing digital processing unit 53 is reduced by the motor rotation speed R = 1, 1/2, 1/4, 1/8, as shown in FIG. Therefore, the power control unit 9 sends a deceleration command to the motor rotation speed changing unit 55 during power saving, lowers the motor rotation speed, sets R = 1, 、, ４, １ ／, and sets the digital processing unit 53. Among them, the clocks of the blocks that do not need to be operated are stopped or the clocks of the blocks that need to be operated, for example, the clock of the recording / reproducing digital processing unit 53 are set to 1 /
By setting them to 2, 1/4, and 1/8, the power consumption of the blocks of the digital circuit can be surely reduced in accordance with the slowing down of the clock. In the analog circuit section of the recording / reproducing section, the power is turned off and power is saved as shown in FIG. Since the other interface unit 54 exchanges data with another circuit block, the internal clock can be reduced, but the external clock cannot be reduced alone. The external clock of this part is supplied to the reference clock generator 5 of the power supply controller 56.
7 must be operated in synchronization with the reference clock of the system.

As for the reference clock of the system, the power control unit 9 receiving the start / stop control signal lowers the clock speed.
The start suspension control signal is issued by the power control unit 102 in the CPU 101 of the computer unit 100 shown in FIG. 13 or FIG. The input / output unit 60 of the interface circuit 59 of the recording / reproducing apparatus 1 is output from the drive start / stop control signal generation unit 104.
, And is detected by the activation suspension control signal detection unit 61 and sent to the power control unit 9.

Power control section 102 of computer section 100
Drive recording / reproducing data monitoring unit 10 provided in
7 constantly monitors the recording / reproducing data amount and frequency between the recording / reproducing apparatus 1 and the computer unit 100, and when the power control unit 102 determines that the data amount and frequency are small, stops and suspends the drive for power saving. , A control signal for standby, speed reduction, and speedup is sent to the drive start / stop control signal generation unit 104 in the interface unit 103.

Returning to the magnetic recording / reproducing apparatus 1, when receiving the above-described start-stop control signal or when a request for recording data or reproduction data is received from the computer 100, the start-stop signal detecting unit 61 sends the power control unit 9 The power control unit 9 sends the information to the cache memory 63 in response to the start / pause instruction.
Monitor the remaining amount of the caches a and 63b. While checking the remaining memory of the cache memory monitor 64,
The clock of the reference clock generation unit 57 or the low-speed clock generation unit 58 is increased / decreased, and the motor rotation speed change unit 55 is controlled so that the rotation speed of the motor 8 is increased / decreased, started / stopped, and the like. Activates / pauses the circuit, speeds up the internal clock of CPU 13 /
The speed is reduced or the power is turned on / off to perform fine power saving control to reduce the power of each unit.

FIG. 10A shows the power saving operation of the present invention.
(B) Conventional power saving operation unit and FIGS. 10 (a) and (b)
The operation will be described in comparison with the power saving operation diagram of the present invention.

First, in the conventional case shown in FIGS. 10A and 10B, a sleep mode is provided. In the sleep mode, the rotation of the motor is stopped, and the power consumption of the motor is reduced. However, at the time of startup, data recording / reproduction cannot be performed at all until the rated rotation is reached, so that a waiting time of 3 to 10 seconds occurs until the reproduction data is obtained.

On the other hand, in the method of the present invention shown in FIGS. 3C and 3D, the cache memory / data rate monitor unit shown in FIG. I have. Therefore, as shown in FIG. 10C, after starting at t = t _1, at t = t ₂ ,
Playback can be started at double speed and access to playback data. At t = t ₂ , the analog circuit of the recording / reproducing unit is ON
The power of the digital circuit is reduced because the digital circuit operates at a low speed clock of 1/4 and the main clock operates at 1/2. At this time, the power control unit 9 lowers the driving force of the track driving unit 19 at the time of the track seek to save power.
Although the track access speed becomes slower, in the first embodiment, the reproduction can be performed even at a low rotational speed, so that there is a power saving effect without substantially increasing the access time. At t = t ₄ , the reproduction ends and recording starts. Exit recorded at t = t _5, and OFF the analog circuit of the recording and reproducing unit, stops the clock of the digital circuit. From t = t _{5 to} t _{6, the apparatus} stands by in the idle state, suspends the operation of the circuit except for the interface section, and saves power. At t = t ₆ , the motor is decelerated to １ ／ and the power is further reduced. Start playback on t = t _8, the if the G sensor 18 as shown in the flowchart of FIG. 16 detects an impact, or if the playback data amount is insufficient accelerated at _{t = t 9, t = t} 11 Full rotation with. Reproducing data is completed to decelerate the motor at t = t _12, and OFF the analog circuit to stop the clock of the digital circuit R =
Reduce to 1/8. The analog circuit is ON at t = t _14, to start playing, to start recording at t = t15. until t = t ₁₆ performs the record, it enters the idle mode. And go into sleep mode when t = t ₁₇ there is no data access,
Move the head to the evacuation track and stop the motor completely. And if there is no fixed time request, OFF causes the power except for the interface unit in t = t _19.

Here, the motor rotation speed and operation clock control routine shown in FIG. 16 will be described. Step 70
a, this routine is started, and in step 70b, the recording / reproducing mode, the remaining amount of the cache memory 63a, the data rate, the power saving command of the personal computer are checked, and the power saving operation table is checked. The ON / OFF of the circuit and the value of the rotational speed R = 1 / n are determined. Set the rotational speed R = 1 / n in step 70c, the motor is rotated at 1 / n in step 70d, it calculates the average detection signal amount S _G G-sensor at step 70e, the rotation this S _G at step 70f G of the number R = 1 / n
Compared with the reference detection signal amount S _G (1 / n) of the sensor, if S _G is much larger than S _G (1 / n) in step 70g, the motor is retracted in step 70j while the head is retracted to the retraction track. To stop. S _G becomes S _G at step 70k
It is checked whether (1 / n) is reached. If NO, the motor is stopped. If YES, the motor is rotated at R = 1 / n.
When NO is returned to step 70g, the process proceeds to step 70h if S _G <S _G (1 / n), that is, G and the G tolerance at the rotation speed are checked.
Is increased to increase the rotational speed to increase the proof stress against G.
Then, it is checked again at step 70h. If YES in step 70h, the average file transfer amount DT required in step 70n is calculated, and step 70p
Then, this D _T is compared with the reference transfer amount D _T (1 / n) from the recording medium at the rotation and speed of R = 1 / n, taking the remaining amount of the recording cache into consideration, and at step 70q, D _T > D _T ( 1
If (/ n) is YES, 1 / n is increased in step 70s, the number of revolutions is increased, the recording / reproducing data rate is increased, and the process returns to step 70q. If NO, the recording / reproducing data rate is sufficient, so the process proceeds to step 70r, where D _T <D _T (1
/ N) That is, it is checked whether the recording / reproducing data rate is too high. If YES, 1 / n, that is, the rotational speed is reduced in step 70r, and the process returns to step 70r. If NO, it is not too large and it is understood that the amount is appropriate, and the process returns to step 70b.

As is apparent from a comparison between FIG. 10B and FIG. 10D, it is possible to obtain a large power reduction and an improvement in access speed. By using the present invention in a magneto-optical disk drive as shown in FIG. 21, the rotational speed can be reduced, and a power saving effect can be obtained. In particular, in the case of the magnetic field modulation method, the flying slider can be caused to fly even at a low speed by the method of the present invention, and at the same time, a large power reduction effect can be obtained by reducing the optical output and performing recording and reproduction. Further, the present invention is applied to other magneto-optical disk drives, phase-change type, CDROM and dye type optical disk drives shown in FIG. And low power optical output enables power-saving recording and reproduction.

[0045]

As described above, the recording / reproducing is performed at an arbitrary rotational speed by using the recording / reproducing motor rotational speed changing unit and the slider having a small flying height variation even if the rotational speed varies in the power control unit. be able to. In this way, even during operation, the power consumption of the motor can be reduced,
Data access time from motor start to data recording / reproduction can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of a recording / reproducing apparatus and a computer unit according to a first embodiment.

2A is a waveform diagram of a motor rotation pulse in the first embodiment. FIG. 2B is a waveform diagram of a reference clock in the first embodiment. FIG. 2C is a waveform diagram of a reproduction signal of the MR head in the first embodiment. Is a waveform diagram of a reproduced signal after differentiation in the first embodiment. (E) is a waveform diagram of a recording / reproducing clock in the first embodiment. (F) is a waveform diagram of a demodulated signal in the first embodiment.

FIG. 3A is a block diagram of a recording / reproducing clock reproducing unit according to the first embodiment. FIG.

4A is a block diagram of a reproduction circuit according to the first embodiment. FIG. 4B is a filter characteristic diagram when R = 1/8 in the first embodiment. FIG. 4C is a block diagram when R = 1/4 in the first embodiment. (D) Filter characteristic diagram when R = の in the first embodiment (e) Filter characteristic diagram when R = 1 in the first embodiment

FIG. 5 is a diagram illustrating a relationship between a PLL pull-in center frequency and a rotation speed of a recording medium according to the first embodiment.

FIG. 6 is a diagram illustrating a relationship between a flying force of a slider and a motor rotation speed according to the first embodiment.

FIG. 7A is a cross-sectional view of a slider section according to the first embodiment. FIG. 7B is a cross-sectional view of the slider section according to the first embodiment.

8A is a diagram illustrating a motor rotation speed, a slider flying height, and a slider pressing force according to the first embodiment. FIG. 8B is a diagram illustrating a motor rotation speed, a slider floating amount, and a slider pressing force according to the first embodiment. ) Shows the motor rotation speed, slider flying height, and slider pressing force in the first embodiment. (D) shows the motor rotation speed, slider floating amount, and slider pressing force in the first embodiment. Diagram showing motor rotation speed, slider flying height, and slider pressing force

FIG. 9 is a top view of a track and a slider arm of a recording medium according to the first embodiment.

10A is a time change diagram of the motor speed in the conventional method. FIG. 10B is a time change diagram of the power consumption in the conventional method. FIG. 10C is a time change diagram of the motor speed in the first embodiment. Fig. 7 is a time change diagram of power consumption in the first embodiment.

FIG. 11 is a perspective view of a recording / reproducing apparatus according to the first embodiment.

FIG. 12 is a cross-sectional view of the track driving unit according to the first embodiment.

FIG. 13 is a perspective view of a personal computer according to the first embodiment.

14A is a cross-sectional view of the slider of the first embodiment. FIG. 14B is a perspective view of the slider of the first embodiment. FIG. 14C is a perspective view of the slider of the first embodiment.

FIG. 15 is a diagram illustrating a relationship between a slider flying height ho and a linear velocity μ according to the first embodiment.

FIG. 16 is a flowchart of a power saving routine according to the first embodiment.

FIG. 17 is a perspective view of the MR head according to the first embodiment.

FIG. 18 is a diagram illustrating a relationship between a linear velocity and an output voltage of the MR head according to the first embodiment.

FIG. 19 is a diagram showing a time change of the motor rotation speed in the first embodiment.

FIG. 20 is a perspective view of a computer unit according to the first embodiment.

FIG. 21 is a block diagram of an optical recording type recording / reproducing apparatus according to the first embodiment.

FIG. 22 is a block diagram of an optical recording type recording / reproducing apparatus according to the first embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Recording / reproducing apparatus (FIG. 1) 2 Recording layer 3 Recording medium 4 Magnetic recording signal 5 Magnetic head 5a MR magnetic head 5b Ring magnetic head 6 Recording / reproducing part 7 Motor drive circuit 8 Rotary motor 8a Rotation generating part 9 Power control part 10 Slider Reference Signs List 11 Flying interval 12 Recording track 13 Central control unit 14 Recording / reproducing track changing unit 15 Slider flying height control unit 16 Slider pressing changing unit 17 Slider spring 18 G sensor 19 Track driving unit 20 Slider arm 21 Arm elevating unit 22 Tracking motor 23 Arm elevating shaft 24 arrow 25 reproducing unit 26 recording clock reproducing section 27 PLL 28 demodulator 29 pull the reference frequency control section 30 VCO 31 frequency divider 32 phase comparator 33 LPF 34 pull the reference frequency 35 LPF 36 frequency f _c changes Instrument 37 Differentiator 38 Punching part 39 Ring head output 40 MR head output 41 MR element 42 Bias voltage part 43 Resistance measuring part 44 Shield 45 Recording part 46 Modulator 47 Recording circuit 48 Recording / reproducing clock reproducing part 49 PLL 51 Spring characteristic 52 Digital processing unit 55 Motor speed change unit 56 Digital unit operation clock change unit 57 Reference clock generation unit 58 Internal clock generation unit 59 Interface circuit 60 Input / output unit 62 Filter characteristics 63 Cashier memory 64 Cache memory monitor unit 65 Evacuation track 67 Spring Power 68 Analog section power control section 69 Memory backup section 100 Computer 101 CPU 102 Power control section 103 Interface section 104 Start / stop signal generation section 105 Keyboard 106 External network Network 107 drive recording / playback data monitor

Claims (5)

[Claims] 1. A magnetic disk, comprising: a rotation motor for rotating the magnetic disk; and a magnetic head for recording information on or reproducing information from the magnetic disk, wherein the rotation motor rotates at a first rotation speed. And a mode for recording and reproducing using the magnetic head, and a mode for recording or reproducing using the magnetic head while the rotating motor rotates at a second rotational speed lower than the first rotational speed. A magnetic recording / reproducing apparatus using a magnetic head having a magnetoresistive sensing element. 2. The magnetic recording / reproducing apparatus according to claim 1, wherein the recording / reproducing head includes a slider. 3. The magnetic recording / reproducing apparatus according to claim 2, wherein a negative pressure slider for stabilizing levitation using a negative pressure is provided as the slider. 4. When the motor rotates at the second rotation speed, a pressure for pressing the slider against the magnetic disk is reduced as compared with when the motor rotates at the first rotation speed. Magnetic recording and reproducing device. 5. The magnetic recording / reproducing apparatus according to claim 2, wherein the second rotation speed is equal to or higher than the rotation speed at which the slider flies above the medium surface of the magnetic disk.